This invention relates generally to wireless communications systems. More particularly, it relates to providing location-based information to mobile communication devices.
As wireless communications rapidly spread into every walk of modern life and approach a state of ubiquity, the demand for the bandwidth (or content) of information transmission in wireless communications networks is also growing. A great deal of effort has been devoted to providing location-specific information to mobile device users in a timely, accurate, interactive, and customized manner, that in turn reduces the bandwidth need and required user interaction.
U.S. Pat. No. 5,636,245, for example, describes a method for determining whether access to particular information transmitted by a broadcaster is appropriate for a particular remote unit (such as a mobile device). The method is particularly useful for distributing situation awareness information. U.S. Pat. No. 5,493,709 discloses a radio receiver using current frequency and coordinate data transmitted by a mobile device as a basis for selecting traffic message pertinent to the user of the device, such that traffic data are automatically selected without requiring traveler""s input. U.S. Pat. No. 5,548,586 discloses a mobile packet communication system and method which are capable of transmitting packet data only to a selected base station in whose service cell a mobile device requesting the data is operating, without transmitting the data to all base stations in the same area. U.S. Pat. No. 5,684,859 discloses a system for providing paging information to roaming subscribers in a convenient and efficient manner to make the change of geographic area as seamless as possible. U.S. Pat. No. 5,898,680 describes a system and method for distributing data (particularly map data and other types of image data) to users by means of a radio frequency link, so that up-to-date data can be obtained as frequently as needed. (In this case, although remote users can obtain data selectively, there is no two-way communication between the users and the source of the data.) U.S. Pat. No. 5,900,825 describes a system and method for providing information to an operator of a vehicle. It requires, however, the vehicle to be equipped with a position determining means (using GPS or signals received from a local transmitter site, for example) and compares the position of the vehicle to the location indicated by each message. When a match is found, the receiver system provides the matching message to the operator. U.S. Pat. No. 5,627,549 describes a system and method for sending specific time and location sensitive advertising information to a moving vehicle. There have also been other efforts on transmitting messages targeted to a specific geographical group of mobile device users, as exemplified by U.S. Pat. Nos. 5,565,909 and 5,432,542.
With prior art systems, the users of mobile communication devices are not allowed to communicate with their respective information service networks in an interactive and personalized manner to tailor information received in the context of their location for example. That is, the information is generic and broadcast to a group of users in the same geographical region, rather than being tailored and targeted to a particular user. Moreover, some of the prior art systems require a third party device, such as a GPS unit, to facilitate generating and delivering the location information.
What is needed in the art, therefore, are innovative ways of delivering accurate location-specific information to mobile device users in an interactive, user-tailored and multimedia fashion without requiring the user""s mobile device to have inherent location capability.
The present invention provides a method for using the RF signal characteristics, or information derived therefrom, of the receiving wireless device to customize the delivery and or content of information to the receiving wireless device, for one or more wireless devices, including, but not limited to, mobile wireless communication devices. In addition, information can be customized by criteria selected by the wireless device user, the information content provider, or the information broadcaster. Customization of information can include generating, modifying, and/or deleting the information content, and regulating the delivery of information content to the mobile device so as to optimize the usage of capacity and decrease the burden on the user.
Information that can be transmitted to wireless devices may reside in a remote database. Information can be content for delivery to wireless devices and criteria to regulate that delivery. Information content can be generic, location and/or velocity centric, and location and/or velocity modified generic data. Examples of generic content are: product promotions, facility usage directions, neighborhood yard sales and events, road and civil construction, and area map information.
Examples of location and/or velocity based content are: mobile device current location, average traffic speed on current or alternate roadway sections, traffic alerts of congested or slow-speed areas, and current directional bearing of travel. An example of location and/or velocity-modified generic content is: dating service based on proximity of wireless device users.
In addition, delivery criteria may be associated with the information content, and can be used to regulate the transmission of the information content. Delivery criteria can be related to the content-provider, the user, and/or the broadcast service provider.
Delivery criteria provided by the information content provider can include, but is not limited to time and duration criteria. Examples of time criteria may include store operation hours associated with particular information content, and time periods associated with scheduled road maintenance. Examples of duration criteria may include the amount of time after content posting to transmit content associated with promotional details in the content, or the amount of time after transmission of the content that the content is valid for, and/or other time-sensitive matters related to the content.
User related delivery criteria may be related to location and personal preferences of the user. Location-related criteria may include, but is not limited to location information, and/or mobile device movement information such as distance, speed, and/or bearing. Examples of location information criteria may include the location of stores selling a product contained in the information content, the location of a traffic accident, or the road containing a traffic accident. Examples of mobile device distance information may include the maximum distance between a mobile device and a store contained in the information content, or the maximum distance between a mobile device and a public danger, such as a traffic incident that may be blocking an exit. An example of mobile device speed information may include a speed range that traffic is moving on a road or highway and information content suitable for highway travelers who may be benefited by the knowledge of that information. An example of mobile device direction information may include information content that can be sent when a receiver is less than a first maximum distance away and conditionally sent if the receiver is less than a second, greater maximum distance and the receiver direction is towards the location associated with the information content.
A mobile device user can provide user-related criteria to information providers or information broadcasters by requesting location-specific information either with an interactive series of one or more requests, or by pre-selecting the type of message to be delivered. Pre-selected conditions for a message may include, time, location, radial distance, commercial services, advertising information, pricing information, traffic conditions or events, and public safety and emergency announcements, to name but a few.
Location of a mobile device is determined using at least one location determining base station site. Information meeting the pre-selected conditions is then transmitted to the mobile device from which a request originated or which was preselected by the user, without imposing any special requirement on the user""s device, or involving a third party (e.g., GPS, or a plurality of base stations). Location-specific information that is time sensitive also can be delivered in real-time or close to real-time. Moreover, location-specific information alternatively can be displayed at a public display unit (such as an electronic billboard), posted on the Internet, or sent to a fax machine, printer, variable message sign, local range radio or a modem. By application of this capability, the present invention also enables an information service network to generate and deliver location-specific information tailored to a plurality of mobile device users.
In accordance with one embodiment of the present invention, an antenna array at a base station receiver of an information service network receives direct path and multipath signals transmitted from a mobile device. The base station determines one or more signal signatures from a subspace of array covariance matrices derived from the received signals. The signature then is compared to a database of calibrated signal signatures and corresponding locations, and a location , which has a calibrated signature best matches the measured signature is selected as the most likely location of the mobile device. In accordance with one embodiment of the present invention, the database of calibrated signal signatures and corresponding locations is generated by a calibration procedure in which a calibration mobile device transmits location data derived from a GPS system to the base station which records the location information together with the signal signature of the calibration device. A more detailed description of this method is given in U.S. Pat. No. No. 6,026,304 issued on Feb. 15, 2000 to Hilsenrath et. al., the entirety of which is incorporated by reference for all purposes.
Knowing the location of the mobile device in an accurate and timely fashion allows the information service network to determine the information that the mobile device user is interested in, and consequently delivers the pertinent information in a timely fashion. The information service network may provide further information to the user in an interactive and user-tailored fashion, or update the information on a regular or a pre-scheduled basis.
In accordance with another aspect of the above location finding method is that it needs only a single base station, in contrast to multiple base stations employed in the prior art methods. Moreover, it does not impose any specific requirement on the mobile device, therefore allowing the wireless network to support all types of mobile devices currently deployed.
Further, the method does not impose a requirement on the mobile device to be communicating with the location network at the time of location determination.
Using a location-finding method of the present invention, traffic density and speed information readily can be generated and continuously updated. Accordingly, real-time traffic information and services, commercial services, and public safety and emergency announcements can be transmitted to mobile device users, displayed at passive display devices (such as electronic billboards) placed in one or more designated areas, or a combination of both. Such information also can be broadcast publicly, posted privately on the Internet, or sent to fax machines or modems.
Furthermore, merchants and information kiosk users can benefit from the ability to send and/or receive location-specific information of interest, such as targeted advertisements and special services, to travelers and shoppers.